1. Field of the Invention
This invention relates to hinges and particularly to a new and improved hinge assembly having relatively few parts and which is compact, easily fabricated and includes overcenter latching capability.
2. Description of the Prior Art
Hinges are commonly employed to provide relative movement between two members of a structure. In particular applications, the weight, cost, compactness and reliability of the hinge becomes particularly important. For example, large structures for use in outer space are folded as compactly as possible in order to fit into a space launch vehicle. Once the vehicle is in space, the structure is removed from the vehicle and unfolded, or deployed. Such large space structures can include many hinges, some or all of which may be required to automatically unfold the members attached to them during the deployment sequence. Additionally, the hinges may have to lock in the unfolded position. Thus, the hinges must have a high degree of reliability.
Although hinges have been previously designed to accomplish the above tasks, such prior art hinges often require a relatively high number of parts, many of which are complex and bulky. The higher number of parts tends to reduce reliability and increase cost. In addition, the heavier weight of the hinges makes them less desirable for space launches by reduction of the effective vehicle payload.
Another disadvantage of many prior art hinges is that they are made of metal. In the temperature extremes of a space environment, such metallic hinges may experience thermal distortion which could reduce the ability of the hinges to properly operate.
An additional disadvantage of many prior art hinges is that they employ external parts or linkages in their drive systems. These external parts or linkages can easily snag wires, cables or antenna reflector surfaces that are mounted on or near and deploy with hinged structural members.
In view of the above-mentioned problems, it is therefore an object of the present invention to provide a hinge assembly which can be easily and comparatively inexpensively fabricated.
Another object of the present invention is to provide a hinge assembly which is light and which has a high degree of reliability through the use of relatively few parts.
Still another object of the present invention is to provide a hinge assembly which is thermally stable.
Yet another object of the present invention is to provide a hinge assembly having a relatively smooth, snag resistant exterior by disposing the drive and latch mechanisms within the interior of the hinge asembly.